全文获取类型
收费全文 | 6683篇 |
免费 | 168篇 |
专业分类
6851篇 |
出版年
2020年 | 63篇 |
2019年 | 75篇 |
2018年 | 406篇 |
2017年 | 316篇 |
2016年 | 362篇 |
2015年 | 116篇 |
2014年 | 104篇 |
2013年 | 1591篇 |
2012年 | 150篇 |
2011年 | 307篇 |
2010年 | 303篇 |
2009年 | 146篇 |
2008年 | 197篇 |
2007年 | 210篇 |
2006年 | 87篇 |
2005年 | 116篇 |
2004年 | 90篇 |
2003年 | 45篇 |
2002年 | 62篇 |
2001年 | 81篇 |
2000年 | 69篇 |
1999年 | 70篇 |
1998年 | 58篇 |
1997年 | 59篇 |
1996年 | 53篇 |
1995年 | 46篇 |
1994年 | 55篇 |
1993年 | 60篇 |
1992年 | 62篇 |
1991年 | 45篇 |
1990年 | 42篇 |
1989年 | 47篇 |
1988年 | 53篇 |
1987年 | 58篇 |
1986年 | 45篇 |
1985年 | 76篇 |
1984年 | 62篇 |
1983年 | 86篇 |
1982年 | 76篇 |
1981年 | 70篇 |
1980年 | 75篇 |
1979年 | 62篇 |
1978年 | 59篇 |
1977年 | 84篇 |
1976年 | 50篇 |
1975年 | 66篇 |
1974年 | 51篇 |
1973年 | 40篇 |
1971年 | 38篇 |
1969年 | 36篇 |
排序方式: 共有6851条查询结果,搜索用时 0 毫秒
81.
82.
83.
KEN G. BREALEY 《The Canadian geographer》1995,39(2):140-156
As social constructions of reality, maps embody the values, truth-claims and power-structures of the cultures that make them. Using a variety of interpretive methodologies, geographers and cartographers have developed the thesis that, through selective 're-presentation', maps 'work' at a discursive, symbolic level. In focusing on the artifact itself, however, they have tended to forget that maps are made by someone. Indeed, as part of a wider institutional network, organized and reified by people in pursuit of certain goals, maps serve to create and sustain territories. In a colonial context, moreover, maps arrest and de-legitimize the territorialization of some cultural groups even as they enfranchise and legitimize that of others. Maps are, in this view, ideological weapons. In this paper I use a materialist hermeneutic to investigate the way in which maps helped to actualize the territorial dispossession of the original inhabitants of what is now British Columbia. Beginning with the charts of George Vancouver and Alexander MacKenzie, and ending with the Indian Reserve maps of the 1916 Royal Commission, I illustrate this thesis by tracing the cartographic encirclement of the Nuxalk and Ts'ilhqot'in First Nations. As an essential adjunct in the Euro-Canadian colonization of the region, the analysis has implications for our understanding of the social, political, and juridical function of maps within contemporary land claims discourse. 相似文献
84.
The issue of fairness often is central within environmental policy debates. The recent proliferation of state and local comparative risk projects for informing the selection of environmental policy priorities offers an appropriate setting to explore the issue of procedural fairness in risk-based decisionmaking. This paper describes and evaluates the process by which one of the initial state comparative risk projects, Washington's “Environment 2010,” attempted to include a broader range of participants in identifying, assessing, and generating preferred management strategies for a wide range of environmental hazards. The Washington case study suggests that comparative risk projects can be fairer procedurally, but that significant barriers remain. Noting that greater procedural fairness does not necessarily produce greater substantive fairness, the paper concludes that more attention needs to be directed at the process by which comparative risk projects translate their consensus upon risk priorities into subsequent actions. 相似文献
85.
Blue glass trade beads from well-dated late seventeenth- to early twentieth-century sites and collections have been analysed non-destructively by instrumental neutron activation analysis. The beads display enough variations in their elemental contents to allow us to characterize the different chemistries. The implication of these results is that similar chemical analyses of blue beads from undated archaeological sites may be used to help date the sites, since each bead chemistry has a specific earliest period. 相似文献
86.
The possibility of lead isotope fractionation in ancient lead production is examined. Kinetic theory relating to isotopic fractionation in non-equilibrium evaporation is considered and the feasibility of the alteration of lead isotope abundance ratios in ore roasting and smelting is assessed. Previous experimental work is shown to have been inconclusive and conclusions are drawn on the need for further research to quantify the possible extent of fractionation in practice. 相似文献
87.
D. E. NELSON G. CHALOUPKA C. CHIPPINDALE M. S. ALDERSON J. R. SOUTHON 《Archaeometry》1995,37(1):151-156
Accelerator mass spectrometry radiocarbon ages have been taken for a test suite of small samples of material removed from some of the ‘beeswax’art figures found in rock shelters in northern Australia. The results indicate that we can reliably date this unique form of rock art with no noticeable damage. We had not expected to find figures of any great antiquity, and so we were surprised to find that the ages obtained spanned the time period from the recent past to about 4000 BP. 相似文献
88.
Richard Morrill 《Geographical analysis》1995,27(1):22-41
As overt racial discrimination lessens and the social and economic status of minorities rises, segregation by class should become more and segregation by race less prominent. This hypothesis is tested via several structural and spatial measures of segregation, for class and for race separately and simultaneously. Even in the ostensibly liberal Seattle, race is found to remain vastly stronger than class for blacks, and even somewhat stronger for Asians. 相似文献
89.
Richard G. Klein 《Journal of World Prehistory》1995,9(2):167-198
The fossil record suggests that modern human morphology evolved in Africa between 150,000 and 50,000 years ago, when the sole inhabitants of Eurasia were the Neanderthals and other equally nonmodern people. However, the earliest modern or near-modern Africans were behaviorally (archaeologically) indistinguishable from their nonmodern, Eurasian contemporaries, and it was only around 50,000-40,000 years ago that a major behavioral difference developed. Archaeological indications of this difference include the oldest indisputable ornaments (or art broadly understood); the oldest evidence for routine use of bone, ivory, and shell to produce formal (standardized) artifacts; greatly accelerated variation in stone artifact assemblages through time and space; and hunting-gathering innovations that promoted significantly larger populations. As a complex, the novel traits imply fully modern cognitive and communicative abilities, or more succinctly, the fully modern capacity for Culture. The competitive advantage of this capacity is obvious, and preliminary dates suggest that it appeared in Africa about 50,000 years ago and then successively in western Asia, eastern Europe, and western Europe, in keeping with an African origin. Arguably, the development of modern behavior depended on a neural change broadly like those that accompanied yet earlier archaeologically detectable behavioral advances. This explanation is problematic, however, because the putative change was in brain organization, not size, and fossil skulls provide little or no secure evidence for brain structure. Other potential objections to a neural advance in Africa 50,000-40,000 years ago or to the wider Out-of-Africa hypothesis, include archaeological evidence (1) that some Neanderthals were actually capable of fully modern behavior and (2) that some Africans were behaviorally modern more than 90,000 years ago. 相似文献
90.
In recent years, cultural anthropologists have made notable progress in understanding the bewildering variety of material exchange transactions found among the aboriginal populations of highland New Guinea. One of the major findings of this work is that competitive exchange behavior may bring in its wake alterations in agronomic practices involving an intensification of production. That intensification is primarily a product of social behavior, rather than an adaptation to climate change or population pressure, is a significant conclusion that should influence the thinking of archaeologists as they investigate past episodes of agronomic change, including the origins of agriculture. 相似文献